Pharaoh’s daughter named him Moses because she said, “I drew him out of the water.” The naming is directly tied to how she found and rescued him. The explanation is given in the narrative itself (Exodus 2:10).
In Exodus 2:8–10 Pharaoh’s daughter accepts the girl’s offer to find a nurse, and the child’s own mother is brought in. The princess instructs her to take the child, nurse him “for me,” and promises to pay her. This scene continues the rescue story begun when Moses’ mother hid him and then placed him in a basket among the reeds, while his sister watched nearby (Exodus 2:1–7). The discovery by Pharaoh’s daughter creates a crisis and an opening: the baby is safe, but his future depends on what the princess will do.
Exodus 2:8–10 shows a tight chain of decisions that turns a life-or-death crisis into a protected arrangement. Pharaoh’s daughter authorizes the girl’s plan (“Go”), the girl brings the baby’s own mother, and the princess commissions her to nurse the child “for me” while paying her wages.
A careful answer keeps the immediate passage, the book's argument, and the whole-Bible storyline together, so the question is answered in context instead of as a detached idea.
Start with Exodus 2:10, then read the surrounding section so the answer stays connected to the passage's flow.
10The child grew, and she brought him to Pharaoh`s daughter, and he became her son. She named him Moses, and said, "Because I drew him out of the water."